Note 9 - Intangible Assets and Goodwill - Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill				$ 19,950				$ 21,037	$ 19,950	$ 21,037
Goodwill acquired									0	12,710
Goodwill impairment charge	$ 0	$ 0	$ 0	$ 0	$ (13,464)	$ 0	$ 0	$ 0	0	(13,464)	$ 0
Translation differences									190	(333)
Goodwill	$ 20,140				$ 19,950				$ 20,140	$ 19,950	$ 21,037

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of transfers into (out of) an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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